The present invention relates to a new and distinct cultivar of Agastache, commonly known as giant hyssop. This hardy perennial is grown for use as an ornamental landscape plant. The new invention will be referred to hereinafter by the cultivar name ‘HEATWAVE’.
‘HEATWAVE’ was discovered by the inventor as a chance seedling in a group of seedlings grown from seeds received in a seed exchange as Monarda austromontana but subsequently identified as unnamed Agastache cana or Agastache mexicana. The pollen parent is unknown. The initial discovery occurred in 1996 at the inventor's nursery in Boskoop, The Netherlands.
The new variety of Agastache ‘HEATWAVE’ is an herbaceous perennial characterized by its height and large bright magenta flowers. ‘HEATWAVE’ is more floriferous than other cultivars and has better winter hardiness.
The closest comparison plants to ‘HEATWAVE’ known to the inventor are Agastache ‘Heather Queen’ (unpatented), Agastache ‘Sinning’ (U.S. Plant Pat. No. 13,673), and Agastache ‘Kiegabi’ (U.S. Plant Pat. No. 16,023). ‘HEATWAVE’ is twice the height of ‘Heather Queen’ or ‘Sinning’. ‘HEATWAVE’ has a darker flower color than ‘Kiegabi’ and is more winter hardy than most other Agastache cana or mexicana cultivars.
The first asexual reproduction of ‘HEATWAVE’ was accomplished in 2001 by the inventor using the method of stem cuttings. The inventor has determined that ‘HEATWAVE’ is a stable variety which reproduces true to type in all successive generations of asexual reproduction.